使用NSAttributedString更改字符串颜色？

6 回答

• 19

  对于 Swift 4:

  var attributes = [NSAttributedStringKey: AnyObject]()
  attributes[.foregroundColor] = UIColor.red
  
  let attributedString = NSAttributedString(string: "Very Bad", attributes: attributes)
  
  label.attributedText = attributedString
  

  对于 Swift 3:

  var attributes = [String: AnyObject]()
  attributes[NSForegroundColorAttributeName] = UIColor.red
  
  let attributedString = NSAttributedString(string: "Very Bad", attributes: attributes)
  
  label.attributedText = attributedString
  

  回复于 2024-04-25T22:32:23+08:00
• 3

  在 Swift 4 ：

  // Custom color
  let greenColor = UIColor(red: 10/255, green: 190/255, blue: 50/255, alpha: 1)
  // create the attributed colour
  let attributedStringColor = [NSAttributedStringKey.foregroundColor : greenColor];
  // create the attributed string
  let attributedString = NSAttributedString(string: "Hello World!", attributes: attributedStringColor)
  // Set the label
  label.attributedText = attributedString
  

  在 Swift 3 ：

  // Custom color
  let greenColor = UIColor(red: 10/255, green: 190/255, blue: 50/255, alpha: 1)
  // create the attributed color
  let attributedStringColor : NSDictionary = [NSForegroundColorAttributeName : greenColor];
  // create the attributed string
  let attributedString = NSAttributedString(string: "Hello World!", attributes: attributedStringColor as? [String : AnyObject])
  // Set the label
  label.attributedText = attributedString
  

  请享用 .

  回复于 2024-04-25T22:32:23+08:00
• 167

  无需使用 NSAttributedString . 您只需要一个带有正确 textColor 的简单标签 . 此外，这个简单的解决方案适用于所有版本的iOS，而不仅仅是iOS 6 .

  但如果您不必要地使用 NSAttributedString ，您可以执行以下操作：

  UIColor *color = [UIColor redColor]; // select needed color
  NSString *string = ... // the string to colorize
  NSDictionary *attrs = @{ NSForegroundColorAttributeName : color };
  NSAttributedString *attrStr = [[NSAttributedString alloc] initWithString:string attributes:attrs];
  self.scanLabel.attributedText = attrStr;
  

  回复于 2024-04-25T22:32:23+08:00
• 111

  使用这样的东西（未编译器检查）

  NSMutableAttributedString *string = [[NSMutableAttributedString alloc]initWithString:self.text.text];
  NSRange range=[self.myLabel.text rangeOfString:texts[sliderValue]]; //myLabel is the outlet from where you will get the text, it can be same or different
  
  NSArray *colors=@[[UIColor redColor],
                    [UIColor redColor],
                    [UIColor yellowColor],
                    [UIColor greenColor]
                   ];
  
  [string addAttribute:NSForegroundColorAttributeName 
                 value:colors[sliderValue] 
                 range:range];           
  
  [self.scanLabel setAttributedText:texts[sliderValue]];
  

  回复于 2024-04-25T22:32:23+08:00
• 23

  你可以创建NSAttributedString

  NSDictionary *attributes = @{ NSForegroundColorAttributeName : [UIColor redColor] };
  NSAttributedString *attrStr = [[NSAttributedString alloc] initWithString:@"My Color String" attributes:attrs];
  

  或NSMutableAttributedString使用范围应用自定义属性 .

  NSMutableAttributedString *attributedString = [[NSMutableAttributedString alloc] initWithString:[NSString stringWithFormat:@"%@%@", methodPrefix, method] attributes: @{ NSFontAttributeName : FONT_MYRIADPRO(48) }];
  [attributedString addAttribute:NSFontAttributeName value:FONT_MYRIADPRO_SEMIBOLD(48) range:NSMakeRange(methodPrefix.length, method.length)];
  

  可用属性：NSAttributedStringKey

  回复于 2024-04-25T22:32:23+08:00
• 4

  使用Swift 4， NSAttributedStringKey 有一个名为 foregroundColor 的静态属性 . foregroundColor 有以下声明：

  static let foregroundColor: NSAttributedStringKey
  

  此属性的值是UIColor对象 . 使用此属性指定渲染过程中文本的颜色 . 如果未指定此属性，则文本将以黑色呈现 .

  以下Playground代码显示如何使用 foregroundColor 设置 NSAttributedString 实例的文本颜色：

  import UIKit
  
  let string = "Some text"
  let attributes = [NSAttributedStringKey.foregroundColor : UIColor.red]
  let attributedString = NSAttributedString(string: string, attributes: attributes)
  

  ---

  下面的代码显示了一个可能的 UIViewController 实现，该实现依赖于 NSAttributedString ，以便从 UISlider 更新 UILabel 的文本和文本颜色：

  import UIKit
  
  enum Status: Int {
      case veryBad = 0, bad, okay, good, veryGood
  
      var display: (text: String, color: UIColor) {
          switch self {
          case .veryBad:  return ("Very bad", .red)
          case .bad:      return ("Bad", .orange)
          case .okay:     return ("Okay", .yellow)
          case .good:     return ("Good", .green)
          case .veryGood: return ("Very good", .blue)
          }
      }
  
      static let minimumValue = Status.veryBad.rawValue
      static let maximumValue = Status.veryGood.rawValue
  }
  

  final class ViewController: UIViewController {
  
      @IBOutlet weak var label: UILabel!
      @IBOutlet weak var slider: UISlider!
      var currentStatus: Status = Status.veryBad {
          didSet {
              // currentStatus is our model. Observe its changes to update our display
              updateDisplay()
          }
      }
  
      override func viewDidLoad() {
          super.viewDidLoad()
  
          // Prepare slider
          slider.minimumValue = Float(Status.minimumValue)
          slider.maximumValue = Float(Status.maximumValue)
  
          // Set display
          updateDisplay()
      }
  
      func updateDisplay() {
          let attributes = [NSAttributedStringKey.foregroundColor : currentStatus.display.color]
          let attributedString = NSAttributedString(string: currentStatus.display.text, attributes: attributes)
          label.attributedText = attributedString
          slider.value = Float(currentStatus.rawValue)
      }
  
      @IBAction func updateCurrentStatus(_ sender: UISlider) {
          let value = Int(sender.value.rounded())
          guard let status = Status(rawValue: value) else { fatalError("Could not get Status object from value") }
          currentStatus = status
      }
  
  }
  

  但请注意，您并不需要使用 NSAttributedString 作为这样的示例，并且可以简单地依赖 UILabel 的 text 和 textColor 属性 . 因此，您可以使用以下代码替换 updateDisplay() 实现：

  func updateDisplay() {
      label.text = currentStatus.display.text
      label.textColor = currentStatus.display.color
      slider.value = Float(currentStatus.rawValue)
  }
  

  回复于 2024-04-25T22:32:23+08:00